Merge the latest default theme CSS into nivo-slider.css since we are only having one theme.
take out demo, themes since we don't want those in Sandvox
convert url( to use nivo-images
take out references to theme-default
trying to bring in some adjustments
fixes for numbers, to not make right-justified anymore (since container  is now outside of the left/right margins of the images) and to get thumbs showing.
fix spacing on dots; center better.
fix CSS so that arrow hovering works properly
merge regular into retina.  Some CSS conflicts due to some things I had started; will need to work in again.